A file recording apparatus which generates data continually is configured to manage files by dividing them in a certain time unit. Thus, the file recording apparatus is operating to store a single file in a non-volatile memory such as a NAND flash memory multiple times. Further, the file recording apparatus also serves to upload metadata related to the file stored in the non-volatile memory when the file is stored. The metadata is a structure storing therein data upon, for example, a position and a size of the file stored in the volatile memory as well as a time when the file is generated and a time when the file is accessed.
As mentioned above, in the file recording medium, metadata regarding a file is stored when the file is stored. Further, in the file recording medium, when an operation such as read/write of a file is performed, metadata of this file is updated. Generally, the update of the metadata does not cause any significant problem because its size is small as compared to wiring actual data included in the file and this updating does not take place frequently.
As for an image file recording apparatus which collects and stores files continually, however, frequent metadata updating may be a problem if this image file recording apparatus uses a non-volatile memory as a storage.
To elaborate, the image file recording apparatus stores image data collected through a camera in the non-volatile memory after converting the image data into a file form. At this time, the image file recording apparatus first stores the image data converted into the file form in a buffer which is located on the memory, and, then, if a certain amount of data is collected, records the image data in the non-volatile memory by performing a flush. Here, in the process of recording the certain amount of data collected in the buffer, the image file recording apparatus updates metadata such as position information of the file data recorded in the storage and the like.
Thus, in the image file recording apparatus, the updating of the metadata may be performed frequently. In the image file recording apparatus using the non-volatile memory such as a NAND flash memory, such a frequent updating of the metadata may cause a reduction in a lifetime of the non-volatile memory and deterioration in a performance thereof.
In this regard, Korean Patent Laid-open Publication No. 10-2015-0071738 (entitled “blackbox for vehicle and method for recording image using same”) discloses a vehicle black box configured to generate a second image data by extracting a brightness component from a first image data which is stored before and after an accident of a vehicle and to transmit the generated second data to a preset external device. Further, this document discloses an image recording method for this vehicle black box as well.